Characteristics; Overload Protection Characteristics - Mitsubishi Electric MELSERVO-J3 Series Instruction Manual

13. CHARACTERISTICS

13. CHARACTERISTICS

13.1 Overload protection characteristics

An electronic thermal is built in the servo amplifier to protect the servo motor, servo amplifier and servo motor
power wires from overloads.
Overload 1 alarm (A50) occurs if overload operation performed is above the electronic thermal relay protection
curve shown in any of Figs 13.1. Overload 2 alarm (A51) occurs if the maximum current flew continuously for
several seconds due to machine collision, etc. Use the equipment on the left-hand side area of the continuous
or broken line in the graph.
In a machine like the one for vertical lift application where unbalanced torque will be produced, it is
recommended to use the machine so that the unbalanced torque is 70% or less of the rated torque. When you
mount the servo amplifier closely, make ambient temperature into 0 to 45°C or use it with 75% or less of
effective load torque.
The MR-J3 series servo amplifiers have the servo motor overload protective function.
(It is set on the basis (full load current) of 115% of the servo amplifier.)
1000
100
Servo-lock
10
1
0.1
0 50 100
(Note 1, 2) Load ratio [%]
MR-J3-10T(1)
Operation
150 200 250 300
1000
100
Servo-lock
10
1
0.1
350 0 50 100
MR-J3-20T(1) to MR-J3-40T(1)
MR-J3-60T(4) to MR-J3-100T(4)
13 - 1
Operation
150 200 250 300
(Note 1, 2, 3) Load ratio [%]
350 400